Total number of deciduous teeth in a 14 yr old child: September 2007

Ans. A: 0 The deciduous dentition is made up of central incisors, lateral incisors, canines, first molars, and secondary molars; there is one in each quadrant, making a total of four of each tooth. All of these are replaced with a permanent counterpa except for the first and second molars; they are replaced by premolars. The deciduous teeth will remain until the age of six. At that time, the permanent teeth sta to appear in the mouth resulting in mixed dentition. The erupting permanent teeth causes root resorption, where the permanent teeth push down on the roots of the deciduous teeth causing the roots to be dissolved and become absorbed by the forming permanent teeth. Mixed dentition is seen upto the age of 12 years and at 14 years there are 28 permanent teeth and no deciduous teeths.